1. Field of the Invention
The present invention relates to radial needle bearings suitably used in, for example, rotational machines, such as electric compressors.
2. Description of Related Art
A known example of a rotational machine equipped with a radial needle bearing is an electric compressor disclosed in Japanese Unexamined Patent Application, Publication No. 2009-293523.
In recent years, there has been a further demand for reducing sound (noise) produced when a rotational machine, such as an electric compressor, is rotated.